Interleukin-24 Research Articles

Effect of iPSC-derived NK cells with site-specific integration of CAR19 and IL24 at the rDNA locus on anti-tumor activity and proliferation.

175 Background: The generation of CAR-NK cells using induced pluripotent stem cells (iPSCs) has emerged as a paradigm for manufacturing off-the-shelf cell products for universal immunotherapy. However, enhancing the potency, safety and multi-actions of CAR-NK cells is still full of challenges. Methods: Interleukin 24 (IL24) and CD19-specific chimeric antigen receptor (CAR19) were site-specifically integrated at the ribosomal DNA (rDNA) locus in human iPSCs by using TALENickases. The engineered iPSCs were differentiated into NK (CAR-iNK) cells by adopting a 38-day differentiation protocol followed by expansion using magnetic beads in vitro. Results: Compared with the CAR-iNK cells, IL24 armored CAR-iNK (CAR19-IL24-iNK) cells showed higher cytotoxic capacity and amplification ability in vitro. Meanwhile, CAR19-IL24-iNK cells inhibited tumor progression more effectively and exhibited better survival without significant side effects in the B-ALL (Nalm-6(Luc1))-bearing mouse model. Interestingly, RNA-sequencing analysis suggested that IL24 may enhance iNK cell function by attracting neutrophils and upregulating FAS and TNFSF10-related genes while exerting a direct effect on tumor cells. Conclusions: This study encourages the exploration of IL24 and other molecules to enhance antitumor properties of CAR-NK cells, suggesting a novel strategy to modulate tumor microenvironment while attacking tumor cells with the potential of promising off-the-shelf immunotherapy.

Enhancement of keratinocyte survival and migration elicited by interleukin 24 upregulation in dermal microvascular endothelium upon welding-fume exposure

ABSTRACT Occupational exposure to welding fumes constitutes a serious health concern. Although the effects of fumes on the respiratory tract have been investigated, few apparent reports were published on their effects on the skin. The purpose of this study was to investigate the effects of exposure to welding fumes on skin cells, focusing on interleukin-24 (IL-24), a cytokine involved in the pathophysiology of skin conditions, such as atopic dermatitis and psoriasis. Treatment with welding fumes increased IL-24 expression and production levels in human dermal microvascular endothelial cells (HDMEC) which were higher than that in normal human epidermal keratinocytes. IL-24 levels in Trolox and deferoxamine markedly suppressed welding fume-induced IL-24 expression in HDMEC, indicating that oxidative stress may be involved in this cytokine expression. IL-24 released from HDMEC protected keratinocytes from welding fume-induced damage and enhanced keratinocyte migration. Serum IL-24 was higher in welding workers than in general subjects and was positively correlated with elevated serum levels of 8-hydroxy-2’-deoxyguanosine, an oxidative stress marker. In summary, welding fumes enhanced IL-24 expression in HDMEC, stimulating keratinocyte survival and migration. IL-24 expression in endothelial cells may act as an adaptive response to welding-fume exposure in the skin.

Serum IL-24 combined with CA125 as screening and prognostic biomarkers for NSCLC.

Noninvasive and effective methods for early screening of non-small cell lung cancer(NSCLC) still need to be developed. At present, a reasonable conclusion is that a combination of tumor markers is a superior predictor of screening. Cytokines, as important regulators of cancer development, have great potential for the screening and prognosis of NSCLC. This study screened novel biomarkers related to the early screening and prognosis of NSCLC. In the present study, the biological significance and immunoregulation of interleukin-24(IL-24) were analyzed based on The Cancer Genome Atlas data. Next, 150 serum samples from initially treated patients with NSCLC and 70 controls were collected, and we obtained pathological sections from 60 patients with NSCLC. The ELISA and immunohistochemistryresults showed the differential expression of IL-24 and carbohydrate antigen 125(CA125). The results show that IL-24 is an important tumor suppressor in NSCLCthat helps to improve the poor prognosis of these patients. A significantly negative correlation between IL-24 and CA125 levels was also found. Notably, serum IL-24 levels were significantly negatively correlated with the TNM stage of patients with NSCLC, consistent with an important role for tumor suppressors in NSCLC. The receiver operating characteristic curve analysis showed that a combination of IL-24 and CA125 was an effective panel for discriminating patients with NSCLC from HD, and individuals with other lung diseases. Serum IL-24 and CA125 levels were identified as independent prognostic markers for NSCLC. The IL-24 and CA125 panel exhibited good performance in the screening of NSCLC.

IPSC-derived NK cells with site-specific integration of CAR19 and IL24 at the multi-copy rDNA locus enhanced antitumor activity and proliferation.

The generation of chimeric antigen receptor-modified natural killer (CAR-NK) cells using induced pluripotent stem cells (iPSCs) has emerged as one of the paradigms for manufacturing off-the-shelf universal immunotherapy. However, there are still some challenges in enhancing the potency, safety, and multiple actions of CAR-NK cells. Here, iPSCs were site-specifically integrated at the ribosomal DNA (rDNA) locus with interleukin 24 (IL24) and CD19-specific chimeric antigen receptor (CAR19), and successfully differentiated into iPSC-derived NK (iNK) cells, followed by expansion using magnetic beads in vitro. Compared with the CAR19-iNK cells, IL24 armored CAR19-iNK (CAR19-IL24-iNK) cells showed higher cytotoxic capacity and amplification ability in vitro and inhibited tumor progression more effectively with better survival in a B-cell acute lymphoblastic leukaemia (B-ALL) (Nalm-6 (Luc1))-bearing mouse model. Interestingly, RNA-sequencing analysis showed that IL24 may enhance iNK cell function through nuclear factor kappa B (NFκB) pathway-related genes while exerting a direct effect on tumor cells. This study proved the feasibility and potential of combining IL24 with CAR-iNK cell therapy, suggesting a novel and promising off-the-shelf immunotherapy strategy.

IL24 Expression in Synovial Myofibroblasts: Implications for Female Osteoarthritis Pain through Propensity Score Matching Analysis.

(1) Introduction: Despite documented clinical and pain discrepancies between male and female osteoarthritis (OA) patients, the underlying mechanisms remain unclear. Synovial myofibroblasts, implicated in synovial fibrosis and OA-related pain, offer a potential explanation for these sex differences. Additionally, interleukin-24 (IL24), known for its role in autoimmune disorders and potential myofibroblast production, adds complexity to understanding sex-specific variations in OA. We investigate its role in OA and its contribution to observed sex differences. (2) Methods: To assess gender-specific variations, we analyzed myofibroblast marker expression and IL24 levels in synovial tissue samples from propensity-matched male and female OA patients (each n = 34). Gene expression was quantified using quantitative polymerase chain reaction (qPCR). The association between IL24 expression levels and pain severity, measured by a visual analog scale (VAS), was examined to understand the link between IL24 and OA pain. Synovial fibroblast subsets, including CD45-CD31-CD39- (fibroblast) and CD45-CD31-CD39+ (myofibroblast), were magnetically isolated from female patients (n = 5), and IL24 expression was compared between these subsets. (3) Results: Females exhibited significantly higher expression of myofibroblast markers (MYH11, ET1, ENTPD2) and IL24 compared to males. IL24 expression positively correlated with pain severity in females, while no correlation was observed in males. Further exploration revealed that the myofibroblast fraction highly expressed IL24 compared to the fibroblast fraction in both male and female samples. There was no difference in the myofibroblast fraction between males and females. (4) Conclusions: Our study highlights the gender-specific role of myofibroblasts and IL24 in OA pathogenesis. Elevated IL24 levels in females, correlating with pain severity, suggest its involvement in OA pain experiences. The potential therapeutic implications of IL24, demonstrated in autoimmune disorders, open avenues for targeted interventions. Notwithstanding the limitations of the study, our findings contribute to understanding OA's multifaceted nature and advocate for future research exploring mechanistic underpinnings and clinical applications of IL24 in synovial myofibroblasts. Additionally, future research directions should focus on elucidating the precise mechanisms by which IL24 contributes to OA pathology and exploring its potential as a therapeutic target for personalized medicine approaches.

Spinal interleukin-24 contributes to neuropathic pain after peripheral nerve injury through interleukin-20 receptor2 in mice

Neuroinflammation is critically involved in nerve injury-induced neuropathic pain, characterized by local and systemic increased levels of proinflammatory cytokines. Interleukin-24 (IL-24), a key member of the IL-10 family, has been extensively studied for its therapeutic potential in various diseases, including cancer, autoimmune disorders, and bacterial infections, but whether it is involved in the regulation of neuropathic pain caused by peripheral nerve injury (PNI) has not been well established. In this study, we reported that spared nerve injury (SNI) induced a significant upregulation of IL-24 in fibroblasts, neurons, and oligodendrocyte precursor cells (OPCs, also called NG2-glia) in the affected spinal dorsal horns (SDHs), as well as dorsal root ganglions (DRGs). We also found that tumor necrosis factor α (TNF-α) induced the transcriptional expression of IL-24 in cultured fibroblasts, neurons, and NG2-glia; in addition, astrocytes, microglia, and NG2-glia treated with TNF-α exhibited a prominent increase in interleukin-20 receptor 2 (IL-20R2) expression. Furthermore, we evaluated the ability of IL-24 and IL-20R2 to attenuate pain in preclinical models of neuropathic pain. Intrathecal (i.t.) injection of IL-24 neutralizing antibody or IL-20R2 neutralizing antibody could effectively alleviate mechanical allodynia and thermal hyperalgesia after PNI. Similarly, intrathecal injection of IL-24 siRNA or IL-20R2 siRNA also alleviated mechanical allodynia after SNI. The inhibition of IL-24 reduced SNI-induced proinflammatory cytokine (IL-1β and TNF-α) production and increased anti-inflammatory cytokine (IL-10) production. Meanwhile, the inhibition of IL-20R2 also decreased IL-1β mRNA expression after SNI. Collectively, our findings revealed that IL-24/IL-20R might contribute to neuropathic pain through inflammatory response. Therefore, targeting IL-24 could be a promising strategy for treating neuropathic pain induced by PNI.

An automatic Darknet-based immunohistochemical scoring system for IL-24 in lung cancer

Immunohistochemical (IHC) detection is of critical importance in the pathological diagnosis of lung cancer. Interleukin-24 (IL-24) is a significant predictive and prognostic marker in IHC detection, which can help to characterize the tumor and predict the clinical course. To determine the score of the IL-24 expression, pathologists will assess the positive area and staining intensity through a microscope and then use a semi-quantitative assessment method to assign a score for each IHC image of lung cancer. However, this process is a time-consuming, imprecise, and subjective process, which can result in inter- and intra-observer discrepancies. Meanwhile, The performance of computer-aided diagnosis (CAD) systems for IHC scoring depends on the quality of manually extracted features. For example, many advanced methods require precise extraction of features of cell nuclei and membranes. However, the complex background and overlapping cells in lung cancer IHC images present significant challenges for segmentation, which can affect the accuracy of the final system's predicted scoring results. In this paper, an automatic Darknet-based IHC scoring system for IL-24 in lung cancer is proposed. Firstly, the original IHC images of lung cancer are blocked and the features are concentrated by a “block attention mechanism, which can reduce the computational burden of the analysis of millions of pixels in IHC images. The blocked images are then inputted into a Darknet-based scoring network, which incorporates a novel feature extraction backbone and loss function to obtain the final scores. To the best of our knowledge, this is the first end-to-end system that directly outputs a clinical score using lung cancer IL-24 IHC images as input. We have constructed a dataset of 5000 manually annotated IL-24 IHC images of lung cancer obtained from the Institute of Life Science and Bioengineering at Beijing Jiaotong University. We will present experimental results to demonstrate the feasibility of our proposed method, which can greatly assist with the clinical diagnosis and treatment of lung cancer.

Suppression of antitumor cytokine IL‑24 by PRG4 and PAI‑1 may promote myxoid liposarcoma cell survival.

Suppression of the antitumor cytokine interleukin-24 (IL-24) is critical for the survival of myxoid liposarcoma (MLS) cells. It has been previously demonstrated by the authors that an MLS-specific chimeric oncoprotein, translocated in liposarcoma-CCAAT/enhancer-binding protein homologous protein (TLS-CHOP), supresses IL24 mRNA expression via induction of proteoglycan 4 (PRG4) to sustain MLS cell proliferation. However, IL-24 has also been revealed to be suppressed by the ubiquitin-proteasome system in human ovarian and lung cancer cells. Therefore, the aim of the present study was to elucidate the mechanism of IL-24 suppression in MLS cells. The results revealed that the proteasome inhibitor, MG-132, induced cell death in MLS cells in vitro; this effect was reduced following IL-24 knockdown. This indicated that proteasomal degradation of IL-24 may be an important process for MLS cell survival. In addition, it was also previously revealed by the authors that knockdown of plasminogen activator inhibitor-1 (PAI-1), a TLS-CHOP downstream molecule, suppressed the growth of MLS cells, thus instigating the investigation of the effect of PAI-1 on IL-24 expression in MLS cells. Double knockdown of PAI-1 and IL-24 negated the growth-suppressive effect of PAI-1 single knockdown in MLS cells. Interestingly, PAI-1 single knockdown did not increase the mRNA expression of IL24, but it did increase the protein abundance of IL-24, indicating that PAI-1 suppressed IL-24 expression by promoting its proteasomal degradation. Moreover, treatment of MLS cells with a PAI-1 inhibitor, TM5275, induced IL-24 protein expression and apoptosis. Collectively, the results of the present as well as previous studies indicated that IL-24 expression may be suppressed at the transcriptional level by PRG4 and at the protein level by PAI-1 in MLS cells. Accordingly, PAI-1 may represent an effective therapeutic target for MLS treatment.

Regulation of IL-24/IL-20R2 complex formation using photocaged tyrosines and UV light.

Human interleukin 24 (IL-24) is a multifunctional cytokine that represents an important target for autoimmune diseases and cancer. Since the biological functions of IL-24 depend on interactions with membrane receptors, on-demand regulation of the affinity between IL-24 and its cognate partners offers exciting possibilities in basic research and may have applications in therapy. As a proof-of-concept, we developed a strategy based on recombinant soluble protein variants and genetic code expansion technology to photocontrol the binding between IL-24 and one of its receptors, IL-20R2. Screening of non-canonical ortho-nitrobenzyl-tyrosine (NBY) residues introduced at several positions in both partners was done by a combination of biophysical and cell signaling assays. We identified one position for installing NBY, tyrosine70 of IL-20R2, which results in clear impairment of heterocomplex assembly in the dark. Irradiation with 365-nm light leads to decaging and reconstitutes the native tyrosine of the receptor that can then associate with IL-24. Photocaged IL-20R2 may be useful for the spatiotemporal control of the JAK/STAT phosphorylation cascade.

A tissue injury sensing and repair pathway distinct from host pathogen defense

Pathogen infection and tissue injury are universal insults that disrupt homeostasis. Innate immunity senses microbial infections and induces cytokines/chemokines to activate resistance mechanisms. Here, we show that, in contrast to most pathogen-induced cytokines, interleukin-24 (IL-24) is predominately induced by barrier epithelial progenitors after tissue injury and is independent of microbiome or adaptive immunity. Moreover, Il24 ablation in mice impedes not only epidermal proliferation and re-epithelialization but also capillary and fibroblast regeneration within the dermal wound bed. Conversely, ectopic IL-24 induction in the homeostatic epidermis triggers global epithelial-mesenchymal tissue repair responses. Mechanistically, Il24 expression depends upon both epithelial IL24-receptor/STAT3 signaling and hypoxia-stabilized HIF1α, which converge following injury to trigger autocrine and paracrine signaling involving IL-24-mediated receptor signaling and metabolic regulation. Thus, parallel to innate immune sensing of pathogens to resolve infections, epithelial stem cells sense injury signals to orchestrate IL-24-mediated tissue repair.

Prognostic Value and Immunological Role of the Interleukin 24 Gene in Pan-Cancer Using the Kaplan-Meier Plotter and GEPIA by Genomic Data Commons and R Programming Software

There exists an exclusive cytokine and tumor suppressor gene, which is called Interleukin 24 (IL-24), in interleukin 10 (IL-10) family with antitumor and immune-activating properties. However, pan-cancer analysis of IL-24 for identifying survival prognosis and tumor immune infiltration level remains lacking. This study utilized multiple online data analysis approaches, including TIMER, Oncomine, GEPIA and the Kaplan-Meier Plotter, for analyzing the differences in expression level, survival and tumor immune infiltration of IL-24 from a pan-cancer perspective. The expression dissection expounded IL-24 was under conveyed inside brain and prostate cancers, etc., but overexpressed in breast, colorectal and gastric cancers, etc. Also, the survival analysis indicated that IL-24 expression was positively linked to subsisting inside breast carcinoma, sarcoma, and lung adenocarcinoma, and negatively correlated with stomach adenocarcinoma, kidney renal papillary cell carcinoma, and uveal melanoma. Then, we selected breast cancer and stomach adenocarcinoma as representative cancers for further study and investigation.We found that IL-24 is obviously associated with the immune cellular infiltration inside breast tumor and stomach adenocarcinoma, where IL-24 is significantly linked to the CD4+ T cell and CD8+ T cell infiltration inside breast cancer. As to the subtypes of breast cancer, IL-24 is evidently linked to CD8+ T cells, B cells and CD4+ T cells in BRCA-basal and BRCA-luminal subtypes. Furthermore, we discovered that IL-24 expression is negatively associated with the tumor mutation burden (TMB) and that there is a higher survival rate with IL-24 overexpression in breast cancer patients with a low TMB. This finding suggests that IL-24 can be a substantial biomarker to predict prognostic value and evaluation of infiltrated immune constituents in several cancers.

Photoregulation of IL-24/IL-20R2 complex formation using a light-responsive non-canonical amino acid.

Human Interleukin 24 (IL-24) is an immunomodulatory cytokine that represents an important target for treatment of autoimmune diseases and cancer. Since the biological functions of IL-24 depend on interactions with its cell membrane receptors, on-demand regulation of the affinity between IL-24 and its cognate partners offers many exciting possibilities in basic research and may have also potential applications in therapy. In particular, control of protein-protein interactions by light has recently found increasing interest. As a proof-of-concept, we developed a strategy based on genetic code expansion technology to photo-control the binding between IL-24 and one of its receptors, IL-20R2. Both these proteins are engineered versions of the native proteins that feature high stability and can be recombinantly expressed in E. coli at adequate yields. Introduction of the photocaged non-canonical amino acid ortho-nitrobenzyl-tyrosine (ONBY) at selected positions of IL-20R2 resulted in severe impairment of heterocomplex assembly as determined by microscale thermophoresis. Irradiation of ONBY-substituted IL-20R2 with UV light (365 nm) reconstitutes the canonical tyrosines and subsequently restores the ability of IL-20R2 to recognize IL-24. We envision that photocontrollable IL-20R2 may be useful for the spatiotemporal regulation of signaling pathways in which IL-24 is involved.

The neutralising and stimulatory effects of antimicrobial peptide LL-37 in human gingival fibroblasts

ObjectivesTo investigate the effects of LL-37, a broad spectrum antimicrobial peptide expressed in periodontal tissues, on human gingival fibroblast responsiveness to microbial challenge and to explore the direct effects of LL-37 on human gingival fibroblasts. DesignThe effect of LL-37 on bacterial lipopolysaccharide-induced expression of Interleukin (IL-6) and chemokine C-X-C motif ligand (CXCL) 8 was determined by enzyme linked immunosorbent assay (ELISA). LL-37′s influence on bacterial lipopolysaccharide-induced IκBα degradation was investigated by western blot. DNA microarray analysis initially determined the direct effects of LL-37 on gene expression, these findings were subsequently confirmed by quantitative polymerase chain reaction and ELISA analysis of selected genes. ResultsBacterial lipopolysaccharide-induced IL-6 and CXCL8 production by human gingival fibroblasts was significantly reduced in the presence of LL-37 at concentrations in the range of 1–10 µg/ml. LL-37 led to a reduction in lipopolysaccharide-induced IκBα degradation by Escherichia coli lipopolysaccharide and Porphyromonas gingivalis lipopolysaccharide (10 µg/ml). LL-37 (50 µg/ml) significantly altered the gene expression of 367 genes in human gingival fibroblasts by at least 2-fold. CXCL1, CXCL2, CXCL3, Interleukin-24 (IL-24), CXCL8, Chemokine (C-C motif) Ligand 2, and Suppressor of Cytokine Signalling 3 mRNA were significantly upregulated by LL-37. LL-37 also significantly stimulated expression of CXCL8, hepatocyte growth factor and CXCL1 at the protein level. ConclusionLL-37 plays an important regulatory role in the immunomodulatory activity of gingival fibroblasts by inhibiting lipopolysaccharide -induced expression of inflammatory cytokines and directly stimulating the expression of an array of bioactive molecules involved in inflammation and repair.

In Silico Investigation of a Chimeric IL24-LK6 Fusion Protein as a Potent Candidate Against Breast Cancer.

Targeted delivery of therapeutic anticancer chimeric molecules enhances the efficacy of drug by improving cellular uptake and circulation time. Engineering the molecules to facilitate the specific interaction between chimeric protein and its receptor is critical to elucidate biological mechanism as well as accuracy in modeling of complexes. A theoretically designed novel protein-protein interfaces can serve as a bottom-up method for comprehensive understanding of interacting protein residues. This study was aimed for in silico analyses of a chimeric fusion protein against breast cancer. The amino acid sequences of the interleukin 24 (IL-24) and LK-6 peptide were used to design the chimeric fusion protein via a rigid linker. The secondary and tertiary structures along with physicochemical properties by ProtParam and solubility were predicted using online software. The validation and quality of the fusion protein was confirmed by Rampage and ERRAT2. The newly designed fusion construct has a total length of 179 amino acids. The top-ranked structure from alpha fold2 showed 18.1 KD molecular weight by ProtParam, quality factor of 94.152 by ERRAT, and a valid structure by a Ramachandran plot with 88.5% residues in the favored region. Finally, the docking and simulation studies were performed using HADDOCK and Desmond module of Schrodinger. The quality, validity, interaction analysis, and stability of the fusion protein depict a functional molecule. The fusion gene IL24-LK6 after cloning and expression in a suitable prokaryotic cell might be a useful candidate for developing a novel anticancer therapy.

Enhancement of recombinant human IL-24 (rhIL-24) protein production from site-specific integrated engineered CHO cells by sodium butyrate treatment

Interleukin-24 (IL-24) has specific inhibitory effects on the proliferation of various tumor cells with almost no toxicity to normal cells. The antitumor activity of recombinant human IL-24 protein produced in mammalian cells is much higher than that of bacteria, but its expression level is extremely low. Sodium butyrate (NaBu) was utilized as a media additive to increase protein expression in Chinese hamster ovary cells. The site-specific integrated engineered cells FCHO/IL-24 were treated with NaBu under different culture conditions (10% and 0.5% serum adherent culture, 0.5% serum suspension culture). First, 3 days of 1 mmol/L NaBu treatment significantly increased rhIL-24 expression level in FCHO/IL-24 cells by 119.94 ± 1.5% (**p < 0.01), 57.49 ± 2.4% (**p < 0.01), and 20.17 ± 3.03% (*p < 0.05) under the above culture conditions. Second, NaBu has a time- and dose-dependent inhibitory effect on FCHO/IL-24 proliferation and induces G0/G1 phase arrest. Under 10% and 0.5% serum adherent culture, G0/G1 phase cells were increased by 11.3 ± 0.5% (**p < 0.01) and 15.0 ± 2.6% (**p < 0.01), respectively. No induction of apoptosis was observed under a high dosage of NaBu treatment. These results suggest that NaBu increases rhIL-24 secretion via inhibiting cell cycle progression, thereby trapping cells in the highly productive G0/G1 phase. Finally, with increasing NaBu dose, glucose concentration increased (**p < 0.01) while lactic acid and ammonia concentrations reduced significantly (**p < 0.01) in 10% and 0.5% serum adherent culture supernatant. RNA-seq showed that NaBu treatment affected multiple tumor and immune-related pathways. In conclusion, NaBu treatment dramatically promoted rhIL-24 production in engineered FCHO/IL-24 cells by altering downstream pathways and inducing G0/G1 cell arrest with little effect on apoptosis.

Adaptation process of engineered cell line FCHO/IL-24 stably secreted rhIL-24 in serum-free suspension culture

Interleukin-24 (IL-24) displays tumor cell-specific proliferation inhibition in vitro and in vivo. Recombinant human IL-24 (rhIL-24) has significantly higher activity, yet significantly lower expression level in mammalian cells than in bacteria. To further realize therapeutic potential of IL-24, we enhanced rhIL-24 expression in mammalian cell systems by adapting engineered Flp-InTMCHO/IL-24 (FCHO/IL-24) cells (adherent cultured in Ham's F12 medium with 10% serum) to serum-free suspension culture. First, MTT assay showed that among four different media (F12, DMEM/F12, 1640 and DMEM), DMEM/F12 medium was the most suitable media for lower-serum adherent culture. Then, cells were adherently cultured in DMEM/F12 with serum concentration reduced from 10% to 0.5% in a gradient manner. Compared to cells in 10% serum, cells in 0.5% serum displayed significantly lower relative cell viability by 40%, increased G0/G1 phase arrest (8.5 ± 2.4%, p < 0.05), decreased supernatant rhIL-24 concentration by 73%, and altered metabolite profiles, such as glucose, lactate and ammonia concentration. Next, the cells were directly adapted to 0.5% serum suspension culture in 125 mL shake flask at 119 rpm with the optimal cell seeding density of 5 × 105 cells/mL (3.3 times higher than that of adherent culture), under which the concentration of rhIL-24 in culture medium was stable at 3.5 ng/mL. Finally, cells adapted to 0.5% serum proliferated better in serum-free medium Eden™-B300S with higher rhIL-24 expression level compared to CDM4CHO. The successful adaptation of engineered cells FCHO/IL-24 laid foundation for adapting cells from adherent culture to suspension serum-free culture to mass produce rhIL-24 protein for therapeutic purposes.

Methyltransferase-like 3 leads to lung injury by up-regulation of interleukin 24 through N6-methyladenosine-dependent mRNA stability and translation efficiency in mice exposed to fine particulate matter 2.5

Fine particulate matter 2.5 (PM2.5) exposure leads to the progress of pulmonary disease. It has been reported that N6-methyladenosine (m6A) modification was involved in various biological processes and diseases. However, the critical role of m6A modification in pulmonary disease during PM2.5 exposure remains elusive. Here, we revealed that lung inflammation and mucus production caused by PM2.5 were associated with m6A modification. Both in vivo and in vitro assays demonstrated that PM2.5 exposure elevated the total level of m6A modification as well as the methyltransferase like 3 (METTL3) expression. Integration analysis of m6A RNA immunoprecipitation-seq (meRIP-seq) and RNA-seq discovered that METTL3 up-regulated the expression level and the m6A modification of Interleukin 24 (IL24). Importantly, we explored that the stability of IL24 mRNA was enhanced due to the increased m6A modification. Moreover, the data from qRT-PCR showed that PM2.5 also increased YTH N6-Methyladenosine RNA Binding Protein 1 (YTHDF1) expression, and the up-regulated YTHDF1 augmented IL24 mRNA translation efficiency. Down-regulation of Mettl3 reduced Il24 expression and ameliorated the pulmonary inflammation and mucus secretion in mice exposed to PM2.5. Taken together, our finding provided a comprehensive insight for revealing the significant role of m6A regulators in the lung injury via METTL3/YTHDF1-coupled epitranscriptomal regulation of IL24.

Oncolytic therapy with vaccinia virus carrying IL-24 for hepatocellular carcinoma

BackgroundHepatocellular carcinoma (HCC) is a highly refractory cancer associated with increasing mortality, which currently lacks effective treatment options. Interleukin-24 (IL-24) is a novel tumor suppressor cytokine that can selectively induce cancer cell apoptosis, and it has been utilized as a cancer gene therapy strategy. The vaccinia virus is a promising strategy for cancer therapy, owing to its direct viral lytic effects, as well as a vehicle to overexpress therapeutic transgenes.MethodsWe constructed a recombinant oncolytic vaccinia viruse (VG9-IL-24) based on vaccinia virus Guang9 (VG9) harboring the IL-24 gene. In vitro, we assessed the replication of VG9-IL-24 in HCC cell lines and normal liver cells and evaluated the cytotoxicity in different cell lines; then, we determined the expression of IL-24 by RT-PCR and ELISA. We examined apoptosis and cell cycle progression in SMMC-7721 cells treated with VG9-IL-24 by flow cytometry. In vivo, we established the SMMC-7721 xenograft mouse model to evaluate the antitumor effects of VG9-IL-24.ResultsIn vitro, VG9-IL-24 efficiently infected HCC cell lines, but not normal liver cells, and resulted in a high level of IL-24 expression and significant cytotoxicity. Moreover, VG9-IL-24 induced an increase in the proportion of apoptotic cells and blocked the SMMC-7721 cell cycle in the G2/M phase. In vivo, tumor growth was significantly suppressed and the survival was prolonged in VG9-IL-24-treated mice.ConclusionsVaccinia virus VG9-mediated gene therapy might be an innovative treatment for cancer with tumor-specific lysis and apoptosis-inducing effects. VG9-IL-24 exhibited enhanced antitumor effects and is a promising candidate for HCC therapy.

Protein kinase R is an innate immune sensor of proteotoxic stress via accumulation of cytoplasmic IL-24.

Proteasome dysfunction can lead to autoinflammatory disease associated with elevated type I interferon (IFN-αβ) and NF-κB signaling; however, the innate immune pathway driving this is currently unknown. Here, we identified protein kinase R (PKR) as an innate immune sensor for proteotoxic stress. PKR activation was observed in cellular models of decreased proteasome function and in multiple cell types from patients with proteasome-associated autoinflammatory disease (PRAAS). Furthermore, genetic deletion or small-molecule inhibition of PKR in vitro ameliorated inflammation driven by proteasome deficiency. In vivo, proteasome inhibitor-induced inflammatory gene transcription was blunted in PKR-deficient mice compared with littermate controls. PKR also acted as a rheostat for proteotoxic stress by triggering phosphorylation of eIF2α, which can prevent the translation of new proteins to restore homeostasis. Although traditionally known as a sensor of RNA, under conditions of proteasome dysfunction, PKR sensed the cytoplasmic accumulation of a known interactor, interleukin-24 (IL-24). When misfolded IL-24 egress into the cytosol was blocked by inhibition of the endoplasmic reticulum-associated degradation pathway, PKR activation and subsequent inflammatory signaling were blunted. Cytokines such as IL-24 are normally secreted from cells; therefore, cytoplasmic accumulation of IL-24 represents an internal danger-associated molecular pattern. Thus, we have identified a mechanism by which proteotoxic stress is detected, causing inflammation observed in the disease PRAAS.

Synergistic inhibitory effects of 5-aza-2'-deoxycytidine and cisplatin on urothelial carcinoma growth via suppression of TGFBI-MAPK signaling pathways.

This study aimed to reveal the gene transcriptional alterations, possible molecular mechanisms, and pathways involved in the synergy of 5-aza-2'-deoxycytidine (DAC) and Cisplatin (CDDP) in urothelial carcinoma (UC). Two UC cell lines, 5637 and T24, were used in the present study. A cDNA microarray was performed to identify critical genes involved in the synergistic mechanism of both agents against UC cells. The results showed that several key regulatory genes, such as interleukin 24 (IL24), fibroblast growth factor 1 (FGF1), and transforming growth factor beta induced (TGFBI), may play critical roles in the synergy of DAC and CDDP in UC. Pathway enrichment suggested that many carcinogenesis-related pathways, such as the ECM-receptor interaction and MAPK signaling pathways, may participate in the synergy of both agents. Our results suggest that TGF-β1 stimulates the phosphorylation of ERK1/2 and p38 by increasing TGFBI expression, and that the TGFBI-MAPK signaling pathway plays an important role in the synergy of DAC and CDDP against UC. Therefore, we revealed the synergistic mechanism of DAC and CDDP in UC. Several key regulatory genes play critical roles in the synergy of combined treatment, and the TGFBI-MAPK signaling pathway may be an important potential target of these two agents.